She says in the wake of the Fukushima nuclear disaster Japan is ramping-up coal fired electricity generation, which could open up opportunities for Hunter mines to increase exports.

"In principal Australia is obviously well positioned to have very big share of that.

"However because of the trends in terms of excess supply reducing prices, Japanese customers naturally are going to attempt to get the best commercial results that they can for them, so yes I think it's going to be a tough period."